-Tricky match-up. also, the one that you will prolly face the most.
-Go for the first Q, stand in the middle of your minion wave, riven will go in for the combo, and push the lane, pop a health pot and wait at the turret for the minion wave to push to you. This one is similar against most AOE dmg dealer to make the wave pushed to you faster.
-Farm safe, try not to give any kill, recall when hitting 6 if you got a lot of gold, staying in lane at this point is rather risky because riven can flash combo to burst you down. Rush frozen heart + ninja tabi.
-When going for a last hit, run toward the minion, and then run back to bait out her Q first, then go back for the last hit.